Piston pump arrangement automatically disabling in absence of inlet liquid

ABSTRACT

A piston pump arrangement that disables operation of the pump in the absence of an inlet liquid and also to a piston pump arrangement useful to discharge liquids from at least two sources and to disable discharge of all of the liquids when supply of liquid from at least one source is empty.

RELATED APPLICATION

This application is a continuation of co-pending U.S. patent applicationSer. No. 15/906,840 filed Feb. 27, 2018 and claims the benefit of 35U.S.C. 120.

SCOPE OF THE INVENTION

This invention relates to a piston pump arrangement that disablesoperation of the pump in the absence of an inlet liquid and also to apiston pump arrangement useful to discharge liquids from at least twosources and to disable discharge of all of the liquids when supply ofliquid from at least one source is empty.

BACKGROUND OF THE INVENTION

Pump arrangements are known in which a liquid is fed by gravity to theinlet of a pump which is operative to discharge the liquid as out anoutlet.

As but one example of the prior art, U.S. Pat. No. 8,071,933 to Ophardt,issued Dec. 6, 2011 illustrates a dispensing system for dispensingliquid, most preferably, hand cleaning fluid from a liquid reservoir.The liquid is gravity fed from a liquid reservoir to a piston pump anddischarged via a piston of the piston pump being reciprocally moved in apiston chamber. The piston is moved by an actuator which engages thepiston and the actuator being moved by the rotation of a motor connectedto the actuator by a centric cam. The reservoir and its attached pistonpump assembly are adapted to be removed and replaced when the liquid inthe reservoir is exhausted. The present applicant has appreciated thedisadvantage with such prior art devices that in a case when the liquidin the reservoir is exhausted, the dispenser is continued to be operatedby a user and with time, the resistance to movement of the piston cansubstantially increase with resulting damage to the motorized activatorassembly including the actuator, the motor and coupling mechanismsbetween the motor and the actuator such as gear arrangements, centriccams and the like. Damage to the actuation system is disadvantageoussince the actuation system is to remain in the dispenser for continueduse for an extensive time without replacement

Prior art dispensers are known which simultaneously dispense a firstliquid from a first liquid source and a second liquid from a secondliquid source. Proper operation of any such prior art devices requirethe simultaneous dilution of both liquids.

A disadvantage of such known devices is that when the source of one ofthe two liquids is exhausted, the pump arrangement continues to dispensethe other liquid with the disadvantage that the resultant product is notthe mixture intended to be discharged.

Prior art devices are known in which two liquids from two sources are tobe simultaneously dispensed and at least one of the liquids in its formprior to mixture has a disadvantage associated with it when dischargedwithout the other liquid. For example, one of the liquids may be aconcentrated cleaner which, by itself, would be hazardous as in beingcorrosive and otherwise detrimental when used alone, and the secondfluid may be a diluent such as, for example, water which when mixed withthe first liquid renders the liquid mixture safe for an intended use.The applicant has appreciated the disadvantage that in a pumparrangement for dispensing both the first concentrate liquid and thesecond diluent concentrate that if the supply of the diluent liquidbecomes empty, the pump arrangement may discharge merely the concentrateliquid presenting a hazardous disadvantage. As well, the applicant hasappreciated the disadvantage that should the supply of the concentrateliquid be empty, the disadvantage arises that the pump arrangement willcontinue to dispense merely the diluent liquid having the disadvantageof the delivering a product which is different than the productintended.

The present inventors have appreciated that known self-dilution pumparrangements that are to discharge two liquids suffer the disadvantagethat they do not provide simple and inexpensive mechanisms to ensurethat when either one of two liquids is exhausted that dispensing of bothliquids is stopped.

In one aspect, the present invention provides a pump arrangementcomprising:

a first piston pump having a first chamber and a first pistonreciprocally movable along a first axis in the first chamber to draw afirst fluid into the first chamber from a first reservoir through afirst conduit opening into the first chamber and discharge the firstfluid out a first outlet,

a first float valve across the first conduit between the first reservoirand the first chamber,

the first float valve including a first float movable between an opencondition and a closed condition,

the first float buoyant in the first fluid,

the first float assuming the open condition when a level of the firstfluid in the first conduit is above a predetermined first fluid floatlevel,

the first float assuming the closed position when a level of the firstfluid in the first conduit is at or below the predetermined first floatlevel,

with the first float in the open condition, the first float valvepermitting for flow in the first conduit from the first reservoir to thefirst chamber,

with the first float in the closed condition, the first float valvepreventing flow in the first conduit from the first reservoir to thefirst chamber,

with the first float in the closed position, reciprocal movement of thefirst piston creates a vacuum condition in first chamber between thefirst float valve and the first piston,

a driving member movable reciprocally parallel to the first axis,

the driving member adapted to be coupled to an actuator which moves thedriving member reciprocally parallel to the first axis,

a releasable juncture arrangement releasably coupling the driving memberand the first piston together, the releasable friction juncturearrangement having a coupled condition and an uncoupled condition,

in the coupled condition, the releasable juncture arrangement couplesthe driving member and the first piston together such that reciprocalmovement of the driving member parallel the first axis moves the firstpiston member parallel the first axis in unison,

in the uncoupled condition, the releasable juncture arrangement does notcouple the driving member and the first piston together such thatreciprocal movement of the driving member parallel the first axis doesnot move the piston member rendering the first piston pump inoperativeto discharge the first fluid by movement of the driving member,

with the releasable juncture arrangement in the coupled position, whenthe vacuum condition in the first chamber is greater than a thresholdseparation vacuum, the releasable juncture arrangement assumes theuncoupled position.

Preferably, the pump arrangement of the first aspect includes a secondpiston pump having a second chamber and a second piston reciprocallymovable along a second axis in the second chamber to draw a second fluidinto the second chamber from a second reservoir through a second conduitopening into the second chamber and discharge the second fluid out asecond outlet,

the second axis parallel to the first axis,

a second float valve across the second conduit between the secondreservoir and the second chamber,

the second float valve including a second float movable between an opencondition and a closed condition,

the second float buoyant in the second fluid,

the second float assuming the open condition when a level of the secondfluid in the second conduit is above a predetermined second fluid floatlevel,

the second float assuming the closed position when a level of the secondfluid in the second conduit is at or below the predetermined secondfloat level,

with the second float in the open condition, the second float valvepermitting for flow in the second conduit from the second reservoir tothe second chamber,

with the second float in the closed condition, the second float valvepreventing flow in the second conduit from the second reservoir to thefirst chamber,

with the second float valve in the closed position, reciprocal movementof the second piston creates a vacuum condition in second chamberbetween the second float valve and the second piston,

a coupling bridge member mechanically linking the first piston and thesecond piston together to form a driven member carrying the first pistonand second piston mechanically linked with the bridge member formovement in unison parallel the first axis,

the driving member coupled to the driven member by the releasablejuncture arrangement,

in the coupled position of the releasable juncture arrangement, thereleasable friction juncture arrangement securing the driving member andthe driven member together for reciprocal movement along the axis inunison,

in the uncoupled position of the releasable juncture arrangement, themovement of the driving member does not move the driven member renderingboth the first piston pump inoperative to discharge the first fluid bymovement of the driving member and the second piston pump inoperative todischarge the second fluid by movement of the driving member,

with the releasable juncture arrangement in the coupled position, wheneither the first vacuum condition is greater than the thresholdseparation vacuum or the second vacuum condition is greater than thethreshold separation vacuum, the releasable juncture arrangement assumesthe uncoupled position.

In a 2^(nd) aspect, the present invention provides a pump arrangementcomprising:

a first piston pump having a first chamber and a first pistonreciprocally movable along a first axis in the first chamber to draw afirst fluid into the first chamber from a first reservoir through afirst conduit opening into the first chamber and discharge the firstfluid out a first outlet,

wherein reciprocal movement of the first piston discharges the firstfluid from the first reservoir until the first reservoir is empty of thefirst fluid wherein further reciprocal movement of the first pistoncreates a vacuum condition in first chamber axially inward of the firstpiston,

a driving member movable reciprocally parallel to the first axis,

the driving member adapted to be coupled to an actuator which moves thedriving member reciprocally parallel to the first axis,

a releasable juncture arrangement releasably coupling the driving memberand the first piston together, the releasable friction juncturearrangement having a coupled condition and an uncoupled condition,

in the coupled condition, the releasable juncture arrangement couplesthe driving member and the first piston together such that reciprocalmovement of the driving member parallel the first axis moves the firstpiston member parallel the first axis in unison,

in the uncoupled condition, the releasable juncture arrangement does notcouple the driving member and the first piston together such thatreciprocal movement of the driving member parallel the first axis doesnot move the piston member rendering the first piston pump inoperativeto discharge the first fluid by movement of the driving member,

with the releasable juncture arrangement in the coupled position, whenthe vacuum condition in the first chamber is greater than a thresholdseparation vacuum, the releasable juncture arrangement assumes theuncoupled position.

In a 3^(rd) aspect, the present invention provides a pump arrangementcomprising:

a first piston pump having a first dispensing chamber and a first pistonelement reciprocally movable along a first axis in the first dispensingchamber to draw a first fluid into the first dispensing chamber from afirst reservoir through a first conduit opening into the firstdispensing chamber and discharge the first fluid out a first dischargeoutlet,

the first piston pump including a first inlet one-way valve across thefirst conduit, the first inlet one-way valve providing for flow of thefirst fluid from the first reservoir to the first dispensing chamber butpreventing flow of the first fluid from the first dispensing chamber tothe first reservoir,

wherein reciprocal movement of the first piston element discharges thefirst fluid from the first reservoir until the first reservoir is emptyof the first fluid wherein further reciprocal movement of the firstpiston element creates a first vacuum condition in first dispensingchamber axially inward of the first piston element,

first piston element including a driven member,

a driving member movable reciprocally parallel to the first axis,

a releasable juncture arrangement releasably coupling the driving memberand the driven member together, the releasable juncture arrangementhaving a coupled condition and an uncoupled condition,

in the coupled condition, the releasable juncture arrangement couplesthe driving member and the driven member together such that reciprocalmovement of the driving member parallel the first axis moves the firstpiston element parallel the first axis in unison,

in the uncoupled condition, the releasable juncture arrangement does notcouple the driving member and the driven member together such thatreciprocal movement of the driving member parallel the first axis doesnot move the piston element rendering the first piston pump inoperativeto discharge the first fluid by movement of the driving member,

with the releasable juncture arrangement in the coupled position, whenthe first vacuum condition in the first dispensing chamber is greaterthan a threshold separation vacuum, the releasable juncture arrangementassumes the uncoupled position.

In a 4^(th) aspect, the present invention provides the pump arrangementof the 3^(rd) aspect, wherein the driving member is adapted to beremovably coupled to an actuator member which moves the driving memberreciprocally parallel to the first axis,

a first float valve across the first conduit between the first reservoirand the first dispensing chamber,

the first float valve including a first float movable between an opencondition and a closed condition,

the first float buoyant in the first fluid,

the first float assuming the open condition when a level of the firstfluid in the first conduit is above a predetermined first fluid floatlevel,

the first float assuming the closed position when a level of the firstfluid in the first conduit is at or below the predetermined first floatlevel,

with the first float in the open condition, the first float valvepermitting for flow in the first conduit from the first reservoir to thefirst dispensing chamber,

with the first float in the closed condition, the first float valvepreventing flow in the first conduit from the first reservoir to thefirst dispensing chamber,

with the first float in the closed position, reciprocal movement of thefirst piston element creates the first vacuum condition in firstdispensing chamber between the first float valve and the first pistonelement.

In a 5^(th) aspect, the present invention provides the pump arrangementof the 4^(th) aspect, the first float valve is across the first conduitbetween the first reservoir and the first inlet one-way valve.

In a 6^(th) aspect, the present invention provides the pump arrangementof any one of the 3^(rd) to 5^(th) aspects, and wherein the firstreservoir is unvented and collapsible.

In a 7^(th) aspect, the present invention provides the pump arrangementof any one of the 3^(rd) to 5^(th) aspects wherein the first reservoiris vented to the atmosphere.

In an 8^(th) aspect, the present invention provides the pump arrangementof any one of the 3^(rd) to 7^(th) aspects including:

a second piston pump having a second dispensing chamber and a secondpiston element reciprocally movable along a second axis in the seconddispensing chamber to draw a second fluid into the second dispensingchamber from a second reservoir through a second conduit opening intothe second dispensing chamber and discharge the second fluid out anoutlet selected from the first discharge outlet and a second outlet,

the second axis parallel to the first axis,

the second piston pump including a second inlet one-way valve across thesecond conduit, the second inlet one-way valve providing for flow of thesecond fluid from the second reservoir to the second dispensing chamberbut preventing flow of the second fluid from the second dispensingchamber to the second reservoir,

wherein reciprocal movement of the second piston element discharges thesecond fluid from the second reservoir until the second reservoir isempty of the second fluid wherein further reciprocal movement of thesecond piston element creates a second vacuum condition in seconddispensing chamber axially inward of the second piston element,

a coupling bridge member mechanically linking the first piston elementand the second piston element together for movement in unison parallelthe first axis and forming the driven member,

in the uncoupled position of the releasable juncture arrangement, themovement of the driving member does not move the driven member renderingboth the first piston pump inoperative to discharge the first fluid bymovement of the driving member and the second piston pump inoperative todischarge the second fluid by movement of the driving member,

with the releasable juncture arrangement in the coupled position, wheneither the first vacuum condition is greater than the thresholdseparation vacuum or the second vacuum condition is greater than thethreshold separation vacuum, the releasable juncture arrangement assumesthe uncoupled position.

In a 9^(th) aspect, the present invention provides the pump arrangementof the 8^(th) aspect including:

a second float valve across the second conduit between the secondreservoir and the second chamber,

the second float valve including a second float movable between an opencondition and a closed condition,

the second float buoyant in the second fluid,

the second float assuming the open condition when a level of the secondfluid in the second conduit is above a predetermined second fluid floatlevel,

the second float assuming the closed position when a level of the secondfluid in the second conduit is at or below the predetermined secondfloat level,

with the second float in the open condition, the second float valvepermitting for flow in the second conduit from the second reservoir tothe second dispensing chamber,

with the second float in the closed condition, the second float valvepreventing flow in the second conduit from the second reservoir to thesecond dispensing,

with the second float valve in the closed position, reciprocal movementof the second piston element creates the vacuum condition in seconddispensing chamber between the second float valve and the second pistonelement.

In a 10^(th) aspect, the present invention provides the pump arrangementof the 9^(th) aspect wherein:

the second float valve is across the second conduit between the secondreservoir and the second inlet one-way valve.

In an 11^(th) aspect, the present invention provides the pumparrangement of the 8th, 9th or 10th aspect wherein the second reservoiris unvented and collapsible.

In a 12^(th) aspect, the present invention provides the pump arrangementof the 8^(th), 9^(th) or 10^(th) aspect wherein the first reservoir isvented to the atmosphere and the second reservoir is vented to theatmosphere.

In a 13^(th) aspect, the present invention provides the pump arrangementof any one of the 3^(rd) to 12^(th) aspects wherein the driving memberand the driven member are mechanically engaged through a frangiblemember that severs when the applied tension force parallel the firstaxis is greater than a threshold tension force parallel the first axis.

In a 14^(th) aspect, the present invention provides the pump arrangementof any one of the 3^(rd) to 12^(th) aspects wherein the driving memberand the driven member are frictionally engaged with frictional forcespreventing disengagement unless the applied tension force parallel thefirst axis is greater than a threshold tension force parallel the firstaxis.

In a 15^(th) aspect, the present invention provides the pump arrangementof any one of the 3^(rd) to 14^(th) aspects wherein the releasablejuncture arrangement is formed by the driving member and the drivenmember being engaged to prevent relative axial movement of the drivingmember relative the driven member by the application across thereleasable juncture arrangement of an applied tension force parallel thefirst axis unless the applied tension force parallel the first axis isgreater than a threshold tension force parallel the first axis.

In a 16^(th) aspect, the present invention provides the pump arrangementof any one of the 8^(th) to 15^(th) aspects wherein:

the first float valve including a first valve seat about a first fluidoutlet opening, in the closed condition, a surface of the first floatsealably engages the first valve seat to prevent flow through the firstfluid outlet opening to the first dispensing chamber, and the firstfloat valve including a first cage structure constraining movement ofthe first float with the first cage structure, the first float movablein the first cage structure between the open condition and the closedcondition,

the second float valve including a second valve seat about a secondfluid outlet opening, in the closed condition, a surface of the secondfloat sealably engages the second valve seat to prevent flow through thesecond fluid outlet opening to the second dispensing chamber, and thesecond float valve including a second cage structure constrainingmovement of the second float with the second cage structure, the secondfloat movable in the second cage structure between the open conditionand the closed condition.

In a 17^(th) aspect, the present invention provides the pump arrangementof any one of the 3^(rd) to 16^(th) aspects wherein the first dispensingchamber having an open outer end,

the first piston element having a distal inner end coaxially slidablewithin the first dispensing chamber about the first axis,

the first piston element extending from the distal inner end outwardlythrough the open outer end of the first dispensing chamber to an outerend of the first piston element carrying the first discharge outlet,

a central passageway through the first piston element from the drivenmember to the driving member open to the first discharge outlet carriedon the driving member.

BRIEF DESCRIPTION OF THE DRAWINGS

Further aspects and advantages of the invention will appear from thefollowing description taken together with the accompanying drawings, inwhich:

FIG. 1 is a schematic cross-sectional front view of a dispenser inaccordance with the first embodiment of the present invention with areservoir filled with a liquid and a piston of a piston pump in anextended position;

FIG. 2 is a view the same as FIG. 1 but with the piston in a retractedposition;

FIG. 3 is a view of the dispenser as in FIG. 1 but with the reservoirempty of the liquid;

FIG. 4 is a view the same as FIG. 3 but showing the piston uncoupledfrom a driving member;

FIG. 5 is a view the same as FIG. 4 but showing the driving member inthe retracted position;

FIG. 6 is a schematic cross-sectional front view of a dispenser inaccordance with the second embodiment of the present invention with tworeservoirs filled with liquids and a piston of a piston pump in anextended position with a driven member and a driving member of thepiston coupled together;

FIG. 7 is a vertical cross-sectional front view of a cartridge as seenin FIG. 6;

FIG. 8 is a vertical cross-sectional front view of a pump arrangement asseen in FIGS. 6 and 7;

FIG. 9 is a schematic cross-sectional front view of the dispenser ofFIG. 6 with a left reservoir empty of liquid and a right reservoirfilled with liquid and the piston of a piston pump in an extendedposition with the driven member and the driving member of the pistonuncoupled;

FIG. 10 is a schematic cross-sectional front view of the dispenser ofFIG. 6 with a left reservoir filled with liquid and a right reservoirempty of liquid and the piston of a piston pump in an extended positionwith the driven member and the driving member of the piston coupled;

FIG. 11 is a cross-sectional schematic front perspective view of acartridge in accordance with a third embodiment of the present inventionwith two reservoirs filled with liquids and a piston of a piston pump inan extended position with a driven member and a driving member of thepiston coupled together;

FIG. 12 is a cross-section perspective view of the pump arrangement ofFIG. 11;

FIG. 13 is an exploded cross-section perspective view of the pumparrangement in FIG. 12;

FIG. 14 is a cross-sectional front view of the pump arrangement of FIGS.11 and 12 with a first float in a closed position, a second float in anopen position and a piston with a driven member and a driving memberuncoupled such that the driven member is separated from the drivingmember and with the driving member shown an extended position;

FIG. 15 is a schematic cross-sectional front perspective viewillustrating a cartridge in accordance with a fourth embodiment of thepresent invention with different reservoir assemblies than in the thirdembodiment of FIG. 11;

FIG. 16 is a schematic cross-sectional front perspective view of areplaceable cartridge in accordance with a fifth embodiment of thepresent invention;

FIG. 17 is a cross-sectional front view of a pump arrangement inaccordance a sixth embodiment of the present invention for use with tworeservoirs with a frangible piston element of a piston pump shown as aunitary member in an extended position with a driven member and adriving member of the piston coupled together with a left float in aclosed position and a right float in an open position;

FIG. 18 is a cross-sectional front view of a pump arrangement in FIG. 17but with the frangible piston element broken into axially spacedportions with an axially inner portion forming a driven member spacedaxially inwardly from and uncoupled from a driving member carryingaxially outer portions;

FIG. 19 is a vertical cross-sectional pictorial front view of thefrangible piston element as seen in FIG. 17 with the frangible pistonelement as a unitary member;

FIG. 20 is vertical cross-sectional pictorial front view of thefrangible piston element as seen in FIG. 18 with the frangible pistonelement broken into axially spaced portions; and

FIG. 21 is a vertical cross-sectional pictorial front view of thedriving member of FIG. 17 other than the axially outer portions of thefrangible piston element.

DETAILED DESCRIPTION OF THE DRAWINGS

Reference is made first to FIG. 1 which schematically shows a verticalcross-sectional front view of a dispenser 10 in accordance with apreferred embodiment of the invention. The dispenser 10 comprises ahousing 12 and a replaceable cartridge 14. The cartridge 14 comprises areservoir 16 containing a fluid 17 and a pump arrangement 18. FIG. 1schematically shows the housing 12 supporting the cartridge 14 ready todispense the fluid 17 from the reservoir 16.

The reservoir 16 comprises a reservoir chamber 20 for holding the fluid17 as, for example, liquid soap, which is to be dispensed. The reservoirchamber is open to the atmosphere by a vent opening 21. A reservoiroutlet 22 is provided through a lowermost wall 23 of the chamber 20 openinto an inlet conduit 26 to the pump arrangement 18. In downstreamsuccession, the pump arrangement 18 provides a float valve 28 and apiston pump 30.

The float valve 28 includes a float 32 buoyant in the fluid 17 andconstrained for movement between an open position shown in FIGS. 1 and 2permitting fluid flow outwardly through the float valve 32 and a closedposition shown in FIGS. 3 to 5 in which, in an absence of the fluid 17with atmospheric air 19 in the inlet conduit 26, the float 32 sealablyengages an annular valve seat 34 coaxially about a float valve outletopening 35 to prevent flow outwardly through the float valve outletopening 35 of the float valve 32 to an inlet 37 to the piston pump 30.

A chamber-forming member 36 of the pump arrangement 18 is fixed at aninner end 37 to the reservoir 16. The chamber-forming member 36 carriesthe inlet conduit 26 and the float valve 28 proximate its inner end 37and a dispensing chamber 38 of the piston pump 30 proximate an openouter end 40. The piston pump 30 includes an inlet one-way valve 44downstream from the float valve 28 between the float valve 28 and thedispensing chamber 38. The one-way valve 44 permits flow outwardly fromthe float valve 28 through the float valve outlet opening 35 into aninner end 76 of the dispensing chamber 38 and prevents flow inwardlyfrom the dispensing chamber 38. The pump arrangement 18 also includes apiston element 42 received in dispensing chamber 38 and coaxiallyreciprocally movably relative to the chamber-forming member 36 in thedispensing chamber 38 about a central axis 74.

Actuator

The housing 12 includes a horizontal support flange 46. The supportflange 46 has a support opening 48 vertically therethrough closed at ablind rear end and open forwardly to the front of the support flange 46.A support slotway 47 extends horizontally from the support opening 48 oneach side from the support opening 48.

An actuator assembly 50 is provided on the housing 12 movable verticallyrelative to the support flange 46 of the housing 12. The actuatorassembly 50 includes an actuator plate 52 mounted to the housing 12 tobe vertically slidable relative the housing 12 guided on a pair ofvertically extending guide rods 53 extending downwardly from the supportplate 46 and through a pair of cylindrical guide bores 54 through theactuator plate 52. The actuator plate 52 has a catch opening 58vertically therethrough open forwardly to the front of the actuatorplate 52.

An electric motor 60 is schematically shown as mounted to the housing 12to rotate a drive wheel 61 about a horizontal axis 62. Motion istransferred from the motor 60 to the drive wheel 61 through a shaft 63and a gear box 64. The drive wheel 61 carries an eccentrically mountedaxially extending cam post 66 received in a front to rear horizontallyextending channel 68 in the actuator plate 52 such that rotation of thedrive wheel 61 moves the actuator plate 52 vertically on the guide rods53 relative the housing 12 between an extended position shown in FIG. 1and a retracted position shown in FIG. 2.

The support opening 48 of the support flange 46 and the catch opening 58on the actuator plate 52 are positioned to permit the cartridge 14 to beslid horizontally, rearward for coupling and forwardly for uncoupling,relative the housing 12 with the chamber-forming member 36 and asupporting flange 70 on the chamber-forming member 36 removably receivedin the support opening 48 and its support slotway 47 of the supportflange 46, and an engagement member 72 on the piston element 42removably received in the catch opening 58 of the actuator plate 52.

With the chamber-forming member 36 received in the support opening 48with the supporting flange 70 of the chamber-forming member 36 receivedin the support slotway 47, the support flange 46 supports thechamber-forming member 36 and thereby the reservoir 16 fixed to thehousing 12 against relative vertical movement. With the engagementmember 72 of the piston element 42 received in the catch opening 58 ofthe actuator plate 52, the piston element 42 is reciprocally movablewith the actuator plate 52 relative the chamber-forming member 36. Withthe engagement member 72 of the piston element 42 engaged with theactuator plate 32, reciprocal movement of the actuator plate 32 betweenthe extended position and the retracted position results incorresponding coaxial reciprocal movement of the piston element 42relative the chamber-forming member 36 which, when the reservoir 12contains the fluid 17, dispenses the fluid 17 from the reservoir 12 outa discharge outlet 89 at an outer end 86 of the piston element 42.

A control mechanism 230 is provided to operate the dispenser 10. Thecontrol mechanism 230 preferably includes a sensor 232 on the housing 12to sense the presence of a user's hand below the discharge outlet 89 andto suitably operate the motor 60 when a user's hand is sensed by thesensor 232 as being below the discharge outlet 89.

Float Valve

The float 32 of the float valve 28 is spherical with a spherical outersurface 108.

The chamber-forming member 36 defines the inlet conduit 26 within anaxially elongate radially inwardly directed cage wall 110. At an axiallyouter end 109 of the cage wall 110, a radially inwardly extendingannular seat flange 111 extends radially inwardly to the float valveoutlet opening 35 with the annular valve seat 34 provided as an axiallyinwardly directed surface 112 of the annular seat flange 111 coaxiallyabout the float valve outlet opening 35 and complementary to thespherical outer surface 110 of the float 32 such that when the inletconduit 26 is empty of the fluid 17 and contains air 19 from theatmosphere and the inlet conduit 26 is orientated with the axis 74vertical as shown in FIGS. 4 and 5 under gravity, the float 32 will siton the annular seat flange 111 with the spherical outer surface 110 insealing engagement with the axially inwardly directed surface 112 toprevent flow axially outwardly there between.

At an axially inner end 113 of the cage wall 110 a number ofcircumferentially spaced spoke-like float stop members 114 are provided,each of which extends radially inwardly from the cage wall 110 to adistal end 115 located at a distance from the central axis 74 less thanthe diameter of the float 28. The float stop members 114 prevent thefloat 32 from moving axially inwardly past the float stop members 114.When the inlet conduit 26 is filled with the fluid 17 and orientatedwith the central axis 74 vertical, the float 32 will float upward withinthe cage wall 110 into engagement with the float stop members 114assuming the open position. A cross-sectional area of the inlet conduit26 normal the axis 74 defined within the cage wall 110 is greater than amaximum cross-sectional area of the float 32 such that other than whenfloat 32 is seated on the annular valve seat 34 fluid 17 may flow pastthe float 32 through the float valve 28. With the float 32 buoyant inthe fluid 17, the float 32 assumes the open position with engagement ofthe ends 115 of the float stop members 114 tending to locate the float32 coaxially within the inlet conduit 26 providing for the passage ofthe fluid 17 axially past the float 32 between the float 32 and the cagewall 110 and through openings between adjacent of the float stop members114.

The float valve 28 includes a cage structure 29 that constrains thefloat 32 for movement between the open position shown in FIG. 1 and theclosed position shown in FIGS. 3 to 5. The cage structure 29 is providedby the chamber-forming member 38 and includes the cage wall 110, theannular seat flange 111 and the float stop members 114 arranged to limitmovement of the float 32 within the axially extending circumferentiallyextending cage wall 110 laterally about float 32 and between the axiallyinwardly directed annular seat flange 111 at the axial outer end 109 ofthe cage wall 110 and the axially outwardly directed float stop members114 at the axial inner end 113 of the cage wall 110.

FIGS. 1 to 5 show fluid 17 with an upper surface of the fluid 17 wherethe fluid interfaces with air 19 from the atmosphere representing avertical height or level 21 of the fluid. The float 32 will assume theclosed condition when the level 21 of the fluid 17 in the inlet conduit26 is below a predetermined closed fluid float level, and the float 32will assume the open condition when the level of the fluid 17 in theinlet conduit 26 is at or above a predetermined open fluid float level.The predetermined closed fluid float level and the predetermined openfluid float level may be expected to be the same albeit this is notnecessary.

Piston Pump

The piston pump 30 illustrated is of the type described in U.S. Pat. No.5,165,577 to Ophardt, issued Nov. 24, 1992, the disclosure of which isincorporated herein by reference.

The piston pump 30 includes the one-way valve 44, the chamber-formingmember 36 and the piston element 42.

One-Way Valve

The chamber-forming member 36 provides the dispensing chamber 38 with aradially inwardly directed side wall 84 coaxial about the central axis74 between the inner end 76 and an open outer end 77 of the dispensingchamber 38.

The one-way valve 44 permits fluid 17 from the reservoir 16 to flowoutwardly into the dispensing chamber 38 but prevents flow from thedispensing chamber 38 inwardly back towards the reservoir 16.

The radially inwardly extending annular seat flange 111 extends axiallyoutwardly as an inner tubular member 116 extending coaxially axiallyinto the inner end 76 of the dispensing chamber 38 providing the floatvalve outlet opening 35 centrally therethrough. The inner tubular member116 ends at a radially end wall 117 with a central hole 118 therethroughand circumferentially spaced openings 119 axially through the end wall117 radially outwardly of the center hole 118.

The one-way valve 44 includes a valve member 120 with a central stem 121carrying at an axial inner end an enlarged plug 122 and, at an axialouter end, a flexible circular disc 123. The disc 123 extends radiallyoutwardly to a distal circumferential edge 124. The valve member 120 issecured to the end wall 117 of the inner tubular member 116 with thecentral stem 121 engaged in the center hole 118 capturing the end wall117 between the plug 122 and the disc 123. The distal edge 124 of thedisc 123 is resilient and biased into engagement with the side wall 84of the dispensing chamber 38 so as to prevent flow axially outwardlybetween the disc 123 and the side wall 84. The distal end 124 of thedisc 123 is resilient to be deflectable axially outwardly and radiallyinwardly when a pressure on the axial inner side of the disc 123 isgreater than a pressure on the axial outer side of the disc 123 so as topermit flow axially outwardly between the disc 123 and the side wall 84.Flow of fluid 17 when permitted by the one-way valve 44 and the floatvalve is through the float valve outlet opening 35 into the innertubular member 116 through the end wall 117 via the openings 119 andaxially outwardly between the disc 123 and the side wall 84.

Piston

The reciprocally movable piston element 42 is coaxially slidablyreceived within the dispensing chamber 38 for reciprocal relativesliding about the axis 74. The piston element 42 has an axiallyextending hollow stem 78. The stem 78 of the piston element 42 extendsfrom the dispensing chamber 38 axially outwardly through the open outerend 77 of the dispensing chamber 38 to the discharge outlet 89 at theouter end 86 of the piston element 42.

The side wall 84 of the dispensing chamber 38 is circular incross-section about the axis 74 and preferably cylindrical.

Three discs are provided on the stem 78 extending radially outwardlyfrom the stem 78 at axially spaced locations. A first inner disc 80 isprovided at an innermost end of the stem 78 spaced axially inwardly froma second outer disc 82 which, in turn, is spaced axially inwardly from athird disc providing the engagement member 72. Both the inner disc 80and the outer disc 82 are coaxially slidable within the dispensingchamber 38.

The inner disc 80 extends radially outwardly from the stem 78 to aresilient outer peripheral edge 81 which is directed axially outwardlyand is adapted to engage the side wall 84 of the dispensing chamber 38to prevent flow axially inwardly yet to deflect to permit flow axiallyoutwardly therepast between the outer peripheral edge 81 and the sidewall 84.

The outer disc 82 is adapted to be axially slidable within thedispensing chamber 38. The outer disc 82 extends radially outwardly fromthe stem 78 to an outer peripheral edge 83 that sealably engages theside wall 84 of the dispensing chamber 38 to prevent flow therepast atleast axially outwardly but preferably both axially inwardly andoutwardly.

An annular compartment 85 is defined between the piston element 42 andthe dispensing chamber 38 axially between the inner disc 80 and theouter disc 82 and radially between the stem 78 and the wall 84 of thedispensing chamber 38.

An outermost portion of the stem 78 is hollow with a central passageway88 extending axially inwardly from the discharge outlet 89 at the outerend 86 of the stem 78 centrally through the stem to a closed inner end129. A radially extending transfer port 131 extends radially through thestem 78 on the stem 78 in between the inner disc 80 and the outer disc82 into the central passageway 88 providing communication between theannular compartment 85 and the central passageway 88.

In a withdrawal stroke, with movement from the retracted position ofFIG. 2 to the extended position of FIG. 1, the volume between theone-way valve 44 and the inner disc 80 increases creating a relativevacuum between the one-way valve 44 and the inner disc 80 that opens theone-way valve 44. While the float 32 is in the open condition, thisrelative vacuum draws fluid 17 from the reservoir 16 through the floatvalve 30 past the one-way valve 44 and into the dispensing chamber 38between the one-way valve 44 and the inner disc 80.

In a retraction stroke, with movement from the extended position of FIG.1 to the retracted position of FIG. 2, the volume between the one-wayvalve 44 and the inner disc 80 decreases as does the volume between theone-way valve 44 and the outer disc 82. This decrease in volumeincreases the pressure between the one-way valve 44 and the inner disc80 closing the one-way valve 44 and forcing fluid located between theone-way valve 44 and the inner disc 80 outwardly past the inner disc 80into the annular compartment 85 between the inner disc 80 and the outerdisc 82 and, hence, through the transfer port 131 into the centralpassageway 88 and through the central passageway 88 to out the dischargeoutlet 89.

With the float 32 in the open condition, reciprocal movement of thepiston element 42 in a cycle of operation between the retracted positionand extended position will successively draw and discharge the fluid 17from the reservoir 16 and dispense the fluid 17 from the dischargeoutlet 89.

Releasable Juncture Arrangement

The piston element 42 is formed by two components, namely, an axiallyinner piston or driven member 90 and an axially outer driving member 91.The driven member 90 and the axially outer driving member 91 arereleasably coupled together by a releasable juncture arrangement 92. Thedriving member 91 has at an inner end 95 an annular socket 93 coaxialabout the axis 74 that opens inwardly at an open inner end 94 of thesocket 93. The driven member 90 has at an outer end 97 an annular plug98. The plug 98 and socket 93 are complementarily sized such that theplug 98 is removably received coaxially in the socket 93 in a frictionfit.

The releasable juncture arrangement 92 has a coupled condition as shownin FIGS. 1 to 3 in which the plug 98 is removably received coaxially inthe socket 93 in a friction fit, and an uncoupled condition as shown inFIGS. 4 and 5 in which the plug 98 is removed from the socket 93.

In the coupled condition as shown in FIGS. 1 to 3, the plug 98 andsocket 93 are engaged so as to form a fluid impermeable seal 100 betweenan outer end 101 of an inner portion 102 of the passageway 88 within thedriven member 90 and an inner end 103 of an outer portion 104, thepassageway 88 within the driving member 91. The socket 93 has a radiallyinwardly directed socket wall surface 105 that carries a radiallyinwardly extending annular 106 with an axially outwardly directed catchsurface. The plug 98 has a radially outwardly directed plug wall surface107 complementary to the socket wall surface 105 and including aradially inwardly extending annular channelway 108 with an axiallyinwardly directed catch surface. In the coupled condition, the annularboss 106 is received in the annular channelway 108 with the axiallyoutwardly directed catch surface in engagement with and opposed to theaxially inwardly directed catch surface.

In the coupled condition shown in FIGS. 1 to 3, the releasable juncturearrangement 92 couples the driven member 90 and the driving member 91together such that reciprocal movement of the driving member 91 parallelthe axis 74 moves the driven member 90 parallel the axis 74 in unison.

In the uncoupled condition of the releasable juncture arrangement 92 asshown in FIGS. 4 and 5, movement of the driving member 91 does not movethe driven member 90.

With the releasable juncture arrangement 92 in the coupled position, thefrictional engagement of the socket 93 and the plug 98 is such thatreleasable juncture arrangement 92 remains in the coupled conditionunless axially directed forces are applied to the driven member 90relative to the driving member 91 to draw the driven member 90 axiallyaway from the driving member 91 greater than a threshold force, in whichcase the frictional engagement of the socket 93 and the plug 98 isovercome, the socket 93 and the plug 98 are axially separated fromengagement with each other and the releasable juncture arrangement 92assumes the uncoupled position with the driven member 90 and the drivingmember 91 axially separated from engagement with each other such as seenin FIGS. 4 and 5.

As seen, the releasable juncture arrangement 92 is on the piston element42 axially intermediate the engagement member 72 and the second outerdisc 82.

Preferably, the plug 98, driven member 90, the socket 93 and the drivingmember 91 of the piston element 42 is each formed from plastic as byinjection molding. Providing the socket 93 on the driving member 91 andthe plug 98 on the driven member 90 to be made from plastic material canbe of assistance in providing inherent resiliency between the plug 98and the socket 93 as will provide for separation under a preferred rangeof axially applied threshold forces.

Operation

Operation of the dispenser 10 is now described with reference to FIGS. 1to 5.

As seen in FIGS. 1 and 2, with the float 32 in the open condition withthe releasable juncture arrangement 92 in the coupled condition couplingthe driven member 90 and the driving member 91 together, reciprocalmovement of the driven member 90 and the driving member 91 togetherrelative the dispensing chamber 38 in a cycle of operation draws thefluid from the reservoir 16 and discharges the fluid 17 from thedischarge outlet 89. That is, in axial reciprocal movement of the pistonelement 42 between extended and retracted positions relative thechamber-forming member 36, fluid 17 is drawn from the reservoir 16 anddispensed out the discharge outlet 89. That is, in the conditions asdepicted in FIGS. 1 and 2, the pump 30 is operative to draw the fluid 17from the reservoir 16 through the float valve 28 which is open and todischarge the fluid out the discharge outlet 89.

With continued operation of the pump 30 in the configurations asdepicted in FIGS. 1 and 2 and repeated discharge of the liquid 17, thelevel 21 of fluid 17 in the reservoir will drop until the level of thefluid 17 in the inlet conduit 26 is below the predetermined fluid floatlevel whereupon the float 32 will move to assume the closed conditionwith the releasable juncture arrangement 92 continuing to couple thedriven member 90 and the driving member 91 together in the coupledcondition as seen in FIG. 3.

With continued movement of the driving member 91 in the configuration asseen in FIG. 3 with the releasable juncture arrangement 92 coupling thedriven member 90 and the driving member 91 together in the coupledcondition, with the float valve 28 preventing flow outwardly, a vacuumcondition below atmospheric pressure will be created within thedispensing chamber 38 axially inward of the piston element 42. Thisvacuum is created axially outwardly of the float valve 28 and betweenthe float valve 28 and the inner disc 80 on the driven member 90. Thevacuum condition will serve to apply axially inwardly directed forces tothe driven member 90 attempting to draw the driven member 90 axiallyinwardly away from the driving member 91. The vacuum condition createdbetween the float valve 28 and the inner disc 80 on the driven member 90will come to be sufficient to apply across the releasable juncturearrangement 92 an axially directed applied force greater than thethreshold force, so as to overcome the frictional engagement of the plug98 and the socket 93 separating the plug 98 from the socket 93 as thereleasable juncture arrangement 92 comes to assume the uncoupledposition such as shown in FIGS. 4 and 5. To state this in anothermanner, when the vacuum condition in the dispensing chamber becomesgreater than a threshold separating vacuum, the releasable juncturearrangement assumes the uncoupled position.

With the dispenser in configurations with the releasable juncturearrangement 92 in the uncoupled position such as shown in FIGS. 4 and 5,reciprocal movement of the driving member 91 does not move the drivenmember 90 and the pump 30 is thus disabled and does not draw ordischarge the fluid 17. The operation of the motor 60 will continue toreciprocally move the driving member 91, however, with the releasablejuncture arrangement 92 in the uncoupled position the driven member 91is not moved.

FIG. 2 shows the driving member 91 in a fully retracted position towhich it is moved by the actuator plate 52. As can be seen in FIG. 4,the driven member 90 has been drawn axially inwardly until axial inwardmovement is stopped by the engagement of the inner disc 80 at the innerend of the driven member 90 with the one-way valve member 120. In FIG.4, the driven member 90 is axially inward from its position in FIG. 2.In FIG. 4, the driven member 90 is axially inwardly such that theaxially outer end 97 of the driven member 90 and the axially inner end95 of the driving member 91 are spaced axially in the fully retractedposition and do not interfere with the cyclical movement of the drivingmember 91 between the fully retracted position and the withdrawnposition. The Figures show that there is a sufficient axial spacingbetween the inner disc 80 at the inner end of the driven member 90 andthe one-way valve member 120 for the driven member 90 to be drawnaxially inwardly when uncoupled from the driving member 91 and have thedriven member 90 avoid engagement by the driving member 91.

Reference is made to FIGS. 6 to 10 which show a second embodiment of adispenser 10 in accordance with the present invention. In describing thesecond embodiment, similar reference numerals are used to the referencenumerals used to describe the first embodiment. In the secondembodiment, pairs of similar function components are provided withcomponents shown on the left side in the Figures referred to as the“first” and components shown on the right side in the Figures referredto as the “second” with the second having a number increased by 100 overthe first.

FIG. 6 illustrates the dispenser 10 as having a housing 12 with ahorizontal support flange 46 with a support opening 48 and a supportslotway 47 identical to that in the first embodiment of FIG. 1. Thehousing 12 carries an actuator plate 52 with a catch opening 58vertically slidable on guide rods 53 also identical to that as shownwith the first embodiment. FIG. 6 schematically illustrates a manualarrangement for movement of the actuator plate 52 that which includes alever 130 pivotally mounted to the housing 12 for pivoting about ahorizontal axis 131. One end 132 of the lever 30 engages a lower surfaceof the actuator plate 52 and another end 133 of the lever 130 ispresented at a location for engagement by a hand of a user to urge thelever 130 downwardly. A coil spring 135 is provided about each of theguide rods 53 to bias the actuator plate 52 to a fully extended positionas stopped by end ferrules 136. Such a manually operated lever 130 andits manner of operation to move an actuator plate is well known and maycomprise, for example, an arrangement such as disclosed in U.S. Pat. No.8,113,388 to Ophardt et al, issued Feb. 14, 2012, the disclosure ofwhich is incorporated herein by reference.

In the embodiment as shown in FIGS. 6 to 10, as best seen in FIG. 7, thecartridge 14 has two reservoirs, namely, a first reservoir 16 and asecond reservoir 116. The first reservoir 16 contains a first fluid 17such as a concentrated liquid, for example, a concentrated handdisinfectant. The second reservoir 116 contains a second fluid 117 suchas a diluent, for example, water. The first reservoir 16 has a firstreservoir outlet 22 connected to a first chamber-forming member 36. Thesecond reservoir 116 has a second reservoir outlet 122 connected to asecond chamber-forming member 136. The two chamber-forming members 36,136 are physically connected together as by a lower connecting flange137 that merges with the circular supporting flange 70 that extendscoaxially outwardly about a central axis 139. The supporting flange 70is adapted to be received in the support slotway 47. The supportingflange 70 supports both the first and second chamber-forming members 36,136 and thereby the first and second reservoirs 16, 116 to housing 12against relative vertical movement.

The first chamber-forming member 36 provides a first inlet conduit 26, afirst float valve 28 with a first float 32, a first one-way valve 44 anda first dispensing chamber 38 functioning identical to those describedwith reference to the first embodiment. The second chamber-formingmember 136 provides a second inlet conduit 126, a second float valve 128to a second float 132, a second one-way valve 144 and a seconddispensing chamber 138 functioning identical to those described withreference to the first embodiment.

A first piston element 42 is slidably received within the firstdispensing chamber 38 for reciprocal relative sliding about a first axis74 parallel to the central axis 139 with the first piston element 42having a first stem 78, a first inner disc 80, a first outer disc 82, afirst central passageway 88 and a first transfer port 131 functionallyidentical to those described with the first embodiment so as to define afirst piston pump 30. Similarly, a second piston element 142 is slidablyreceived within the second dispensing chamber 138 for reciprocalrelative sliding about a second axis 174 parallel to the first axis 74with the second piston element 142 having a second stem 178, a secondinner disc 180, a second outer disc 182, a second central passageway 188and a second transfer port 231 functionally identical to those describedwith the first embodiment so as to define a second piston pump 130.

The first stem 78 and the second stem 178 are fixedly connected togetherby a bridge member 141 for movement in unison parallel each of thecenter axis 139 and the first axis 74 and the second axis 174. Thebridge member 141 carries an outwardly extending annular plug 98coaxially about the center axis 139.

An axially outer driving member 91 is provided. The driving member 91has at an inner end an annular socket 93 coaxial about the center axis139 that opens axially inwardly at an open inner end 94 of the socket93. The plug 98 of the bridge member 141 and the socket 93 of the drivenmember 90 are complementarily sized such that the plug 98 is removablyreceived coaxially in the socket 93 in a friction fit. The drivingmember 91 has a first fluid socket 143, a second fluid socket 145 and adischarge passage 147. The passage 147 is open at an outer end as adischarge outlet 89. The first fluid socket 143 is connected with thedischarge passage 147 by a first fluid outlet port 149 and the secondfluid socket 145 is connected to the discharge passage 147 by a secondfluid transfer port 151. The first fluid socket 143 opens inwardly at anopen inner end 153 which is adapted to receive in a sealable engagementan outer end 155 of the first stem 78. The second fluid socket 145 opensinwardly at an open inner end 157 which is adapted to receive in asealable engagement an outer end 255 of the second stem 178.

The first piston element 42 and the second piston element 142 are joinedtogether by the bridge member 141 and together form a driven member 90.The driven member 90 and the axially outer driving member 91 arereleasably coupled together by a releasable juncture arrangement 92. Thereleasable juncture arrangement 92 is comprised of the engagement of thecoupling socket 93 with the coupling plug 98 as well as the sealableengagement of the first stem 78 in the first fluid socket 143 and thesecond stem 178 in the second fluid socket 145. In the coupled conditionas shown on FIGS. 6, 7 and 8, the releasable juncture arrangement 92couples the driven member 90 and the driving member 91 together suchthat reciprocal movement of the driving member 91 parallel the axis 74moves the driven member 90 parallel the axis 74 in unison tosimultaneously operate the first piston pump 30 and the second pistonpump 130 to draw and discharge the first fluid 17 from the first socket143 and the second fluid 117 from the second socket 145 for simultaneousdischarge from the discharge outlet 98. Operation of the first pump 30and the second pump 130 to draw and discharge the first fluid 17 and thesecond fluid 117 simultaneously occurs when, as shown in FIG. 6, each ofthe first reservoir 16 and the second reservoir 116 is sufficiently fullof liquid such that each of the first float 32 and the second float 132are in the open condition as seen in FIGS. 6, 7 and 8.

With the discharge of the first fluid 17 and the second fluid 117 fromthe respective reservoirs, conditions can arise from which as shown inFIG. 9, the first float 32 is in a closed position and the second float132 is in an open position or, as shown in FIG. 10, the first float 32is in an open condition and a second float 132 is in a closed condition.When either of the conditions of the floats are in a closed positionwith the releasable juncture arrangement 92 in a coupled position, thatis, with the driven member 90 coupled to the driving member 91, thenwith continued reciprocal movement of the driving member 91, a vacuumwill be caused to be created in the case that the first float valve 28is closed axially inwardly from the first piston element 42 sufficientlystrong to overcome the frictional engagement of the releasable juncturearrangement 92 as to apply axially directed forces to the driven member90 to draw the driven member 90 away from the driving member 91 greaterthan the frictional forces holding the driving member 91 and the drivenmember 90 together. As a result, the driven member 90 will be drawnaxially inwardly from the driving member 91 uncoupling the releasablejuncture arrangement 92, thus axially separating the driven member 90from the driving member 91 as shown in FIG. 9.

Similarly, in the case that the second float valve 128 is closed, withthe driven member 90 and the driving member 91 coupled together withcontinued reciprocal movement of the driving member 91 a vacuum will becreated in the second pump 130 which will draw the driven member 90axially away from the driving member 91 sufficient to uncouple thedriven member 90 and the driving member 91 placing the releasablejuncture arrangement 92 in the uncoupled condition as shown in FIG. 10.

In the second embodiment of FIGS. 6 to 10, two reservoirs are providedwith two pumps for discharge of fluid from two reservoirs. In the eventthat the liquid in either of the two reservoirs drops to a level below athreshold fluid level for the float valve for one of the two pumps, thena vacuum condition will be created which will sever the driven member 90from the driving member 91 and thereby prevent continued discharge fromboth reservoirs since the movement of the driving member 91 will nolonger move with the driven member 90.

The second embodiment of FIGS. 6 to 10 illustrates an arrangement fordischarge of fluid from two reservoirs with two piston pumps. It is tobe appreciated that similar arrangements may provide for discharge fromthree or more reservoirs with a separate piston pump for each reservoirand with each of the pumps connected to a driven member 90 which willbecome uncoupled from a driving member should a respective float valveleading to any one of the pumps assume a closed condition.

Use of the pump arrangement 18 of FIG. 6 in a manual dispenser isparticularly advantageous to prevent the continued discharge when atleast one reservoir is empty of liquid since it avoids the need forincluding other mechanisms for monitoring of the relative levels offluid in one or more of the reservoirs.

Reference is made to FIGS. 11 to 14 showing a third embodiment of acartridge 14 in accordance with the present invention. FIG. 11 is across-sectional pictorial view illustrating a cartridge 14 comprising afirst reservoir 16 and a second reservoir 116 which two reservoirs 16,116 are identical to those illustrated in FIGS. 6 and 7 in respect ofthe second embodiment.

In the third embodiment of FIGS. 11 to 14, a first chamber-formingmember 36 and a second chamber-forming member 136 are identical to thoseshown in the second embodiment of FIGS. 6 to 9 but for the exceptionthat the separating flange 70 extends radially outwardly about thecenter axis 139 to support an outer tubular member 164 which extendsaxially outwardly from the supporting flange 70 to an open end 166. Anair chamber 168 is defined axially outwardly of the supporting flange 70inwardly of the outer tubular member 164. As can be best seen in FIG.13, the first chamber-forming member 36, the second chamber-formingmember 136, the supporting flange 70 and the outer tubular member 164together comprise a chamber-forming member 169 which is preferablyintegrally formed from plastic as a unitary component.

In the third embodiment of FIGS. 11 to 14, the first and second floatvalves 28, 128, the first and second floats 32, 132 and the first andsecond one-way valves 44, 144 are identical to those illustrated in thesecond embodiment of FIGS. 6 to 10. As well, in the third embodiment ofFIGS. 11 to 14, the driven member 90 is identical to the driven member90 illustrated in the second embodiment of FIGS. 6 to 10.

In the third embodiment of FIGS. 11 to 14, the driving member 91 has anumber of features which are the same as in the second embodiment ofFIGS. 6 to 10. As can be seen in the exploded view of FIG. 13, thedriving member 91 is shown as formed for convenience of manufacture fromtwo elements, namely, an intermediate stem portion 170 and an outermember 173. The outer member 172 provides an outer stem portion 173 fromwhich an air disc 176 extends radially outwardly and axially inwardly toa resilient radially outer peripheral edge 178 which is adapted toengage an interior side wall 180 of the outer tubular member 164 toprevent flow at least axially outwardly therepast but preferably bothaxially inwardly and axially outwardly therepast. The air disc 176 isalso shown to carry a secondary air seal disc 181 that also extendsradially outwardly to a peripheral edge 182 which is directed axiallyoutwardly and is also adapted to engage the side wall 180 of the outertubular member 164 to assist in preventing flow axially inwardlytherepast. Additionally, the air disc 176 includes a radially outwardlyextending guide flange 183 adapted to be located in sliding engagementwith the side wall 180 of the outer tubular member 164 to assist incoaxially locating the driving member 91 coaxially within the outertubular member 164 and, as well, to engage a radially inwardly extendingstop flange 184 on the outer tubular member 164 to limit axial outwardmovement of the driving member 91 relative to the outer tubular member164.

The outer stem portion 173 carries a radially outwardly extendingengagement member 72, the same as in the first and second embodiments aswell as a discharge passage 148 leading to a discharge outlet 89, thesame as in the second embodiment of FIG. 6. Inwardly from the dischargepassage 148, the outer stem portion 173 provides a cylindrical foamgenerator chamber 185 within which there is received a circular outerfoam generating screen 186 and a cylindrical spacing tube 187. At anaxial inner end of the foam generator chamber 185, the outer stemportion 173 provides a radially outwardly extending annular channelway188.

The intermediate stem portion 170 has an axial outer end 189 and anaxially inner end 190. At the axially outer end 189, the intermediatestem portion 170 carries an annular tube 191 carrying a radiallyoutwardly extending boss which is adapted to snap-fit into the annularchannelway 188 in the outer stem portion 174 to secure the intermediatestem portion 170 to the outer stem portion 174 in a snap-fit againstremoval under normal forces occurring during operation of the pumparrangement 18.

At the inner end 190 of the intermediate stem portion 170, theintermediate stem portion 170 carries a first fluid socket 143 and asecond fluid socket 145 as well as a coupling socket 93 identical tothat illustrated in the second embodiment of FIGS. 6 to 11 so as toprovide in the same manner as illustrated in FIGS. 6 to 11 a releasablejuncture arrangement 92 between the socket 93 on the driving member 91and the plug 48 on the driven member 90. The intermediate stem portion170 has a central passageway 191 extending axially therethroughcoaxially about the center axis 140 to receive the first fluid 17 fromthe first fluid socket 143 and the second fluid 17 from the second fluidsocket 145 via the first outlet port 150 and the second outlet port 150.

As seen in FIG. 12, with the driven member 90 coupled to the drivingmember 91 in the extended position as shown in FIG. 12, the air disc 176is received within the air chamber 168 of the outer tubular member 164and an air compartment 192 is formed within the air chamber 168 whosevolume varies with reciprocal movement of the driven member 90 anddriving member 91 while the driven member 90 and the driving member 91are coupled together. An annular liquid sump 193 is defined within thedriving member 91 annularly about the intermediate stem portion 170radially inwardly of axially extending portions of the air disc 176. Twoair ports 193 are shown as extending through a wall of the intermediatestem portion 170 from the liquid sump 193 to the central passageway 191within the intermediate stem portion 170. The liquid sump 193 forms aportion of the air compartment 192. The outer end of the centralpassageway 191 through the intermediate stem portion 170 opens at anoutlet opening 194 open to the foam generator chamber 185.

With the driving member 91 coupled to the driven member 90, reciprocalmovement of the driving member 91 in a retraction stroke from theextended position of FIG. 12 to a retracted position, decreases thevolume in the air compartment 192 discharging any air and liquid withinthe air compartment 192 and its liquid sump 193 through the air ports193 into the central passageway 191. Simultaneously, in the retractionstroke, the first pump 30 and the second pump 130 each discharge thefirst liquid 17 and the second liquid 117 from the first fluid socket143 and the second fluid socket 145 into the central passageway 191. Asa result in a retraction stroke, there is simultaneous discharge of thefirst fluid, the second fluid and air from the air compartment 191 tothe foam generator chamber 185 and through the foam generator where theyare mixed and form a mixture of the liquids and air discharged out thedischarge outlet 898. In a withdrawal stroke, in moving from a retractedposition to the extended position of FIG. 12, the volume of the aircompartment 195 increases drawing atmospheric air in via the dischargeoutlet 89 through the foam generator into the central passage 192 andthrough the air ports 194 into the air compartment 195.

With the driving member 91 coupled to the driven member 90, reciprocalmovement of the driven member 90 draws then discharges the first fluid17 from the first reservoir 16 and the second fluid 117 from the secondreservoir 116 out the discharge outlet as a foam admixed with airdischarged from the air compartment 195.

The third embodiment effectively provides an air pump 196 comprising theair disc 176 within the air chamber 118.

As the first liquid and the second liquid are dispensed, conditions willcome to arise in which the liquid in the first reservoir or the liquidin the second reservoir is discharged until the level of fluid in eitherreservoir drops to a level that one of the first float and the secondfloat assume the closed position. On either the first float or thesecond float assuming the closed condition, continued movement of thedriving member 91 with the driving member 91 and driven member 90coupled will create a vacuum within one of the first pump 30 and thesecond pump 130 sufficient to draw the driven member 90 axially inwardlyrelative to the driving member 91 to separate the driven member 90 fromthe driving member 91 in the same manner that occurred as described withreference to the second embodiment of FIGS. 6 to 10.

FIG. 14 illustrates a condition of the pump arrangement 18 of the thirdembodiment in which the first float 32 is in a closed condition and thedriving member 91 has been drawn axially inwardly by vacuum createdwithin the first dispensing chamber 38 so as to cause uncoupling of thereleasable juncture arrangement 92 and separation of the driven member90 from the driving member 91. The driving member 91 is shown in anuncoupled extended position in FIG. 14. With the third embodiment aswith the second embodiment, should the second float 132 be in the closedcondition, then with continued movement of the driving member 91 coupledto the driven member 90, vacuum would be created which would cause theseparation of the driven member 90 from the driving member 91 as in thesecond embodiment.

Reference is made to FIG. 15 which illustrates a fourth embodiment of acartridge 14 in accordance with the present invention. In FIG. 19, thepump arrangement 18 is identical to the pump arrangement illustrated inFIG. 14 with the exception that the axial extent of the secondchamber-forming member 136 has been reduced. A first reservoir 16 isillustrated as providing a compartment 200 annularly about a center axis139 albeit of a generally rectangular profile as seen in top view. Thesecond reservoir 116 is illustrated as having a cylindrical neck 201leading to its outlet 202 and with a socket 203 for the cylindrical neck201 being formed within the first reservoir 16 coaxially about thecentral axis 139. The second reservoir 116 is shown as being symmetricalabout the central axis 139 and preferably comprises a conventionalbottle of a type used to contain water. The second reservoir 116preferably has its neck 201 sealably removably received within thesocket 203 formed in the first reservoir 16. While not shown for thepurposes of illustration, the connection between the neck 201 of thesecond reservoir 116 and the socket 243 of the first reservoir 16 may bea threaded connection with a suitable sealing arrangement provided.

In accordance with the fourth embodiment, the first reservoir 16containing the first fluid 17 may be secured to the pump arrangement 18and shipped as a unit with the first reservoir 16 containing a firstliquid 17 to be dispensed such as, for example, concentrated liquidsoap. Separately, the second reservoir 116 may be provided or procured,either shipped separately or representing a conventional water bottlereadily commercially available to a user. Alternatively, the arrangementmay be shipped with the second reservoir empty and, on site, the secondreservoir may be filled with a liquid such as tap water and then securedto the first reservoir. Providing for the separate supply of the secondreservoir with preferred liquids such as water having any knownimpurities, it is advantageous and the configuration of the secondreservoir can facilitate easy shipment and handling in a minimal spaceand conventional packaging.

Reference is made to FIG. 16 which illustrates a cross-sectionalperspective view of a cartridge 14 in accordance with a fifth embodimentof the present invention.

In the fifth embodiment of FIG. 16, the pump arrangement 18 is identicalto the pump arrangement 18 illustrated in FIG. 12. Each of the firstreservoir 16 and the second reservoir 116 is formed as a collapsiblebag. The first reservoir 16 and the second reservoir 116 are formed fromtwo mirror image opposed thin sheets of plastic sheeting, only one sheet209 being shown, which opposed sheets 209 are sealed together at lateralsides 210, 211 and along three lateral bands 212, 213 and 214. At alower lateral band 212, a lower plug member 216 is sealingly engagedbetween the two sheets. The lower plug member 216 has two axiallyextending openings, one to sealably engage the first chamber-formingmember 36 and the other to sealably engage the second chamber-formingmember 136. An upper plug member 218 is secured within the upper lateralband 213. The upper plug 218 has a single opening to sealingly engagethe second chamber-forming member 136. The inner end of the firstchamber-forming member 36 opens into the first reservoir 16. The innerend of the second chamber-forming member 136 opens into the secondreservoir 116. The upper lateral band 214 is sealed to a threaded neckplug 220 adapted to removably secure a threaded cap 221 and provide adouble opening to the second reservoir 116.

The cartridge 14 as shown in FIG. 16 is preferably shipped with thefirst reservoir 16 filled with a first fluid but the second reservoir116 unfilled. At a location where the cartridge 14 is to be used, thesecond reservoir 116 is filled with the second fluid such a water viathe cap 221.

In the fifth embodiment illustrated in FIG. 16, the pump arrangement 18is shown to include a first float 32 and a second float 132. However,insofar as the first reservoir is not vented but provides a collapsiblereservoir, once the first fluid is pumped out of the first reservoir 16,further operation of the first pump 30 will result in a vacuum beingcreated within the first reservoir 16 which vacuum is sufficient touncouple the releasable juncture arrangement 92. In the embodiment ofFIG. 16, the first float 32 is not necessary and the first float 32 andthe first float valve 30 may be eliminated. Similarly, in FIG. 16insofar as the second reservoir 116 may not be vented but is a closedcollapsible reservoir, then the second float 132 and the second floatvalve is also unnecessary. In FIG. 16, the provision of the firstreservoir to be collapsible and not vented without a float valve 28 andthe second reservoir 116 which is also collapsible and not vented or maybe vented may preferably be provided to include the second float valve128 out of caution that the cap 221 may leak. It is to be appreciatedthat a collapsible container such as that illustrated for the firstreservoir in FIG. 16 could be used in conjunction with a non-collapsiblesecond reservoir 16 such as illustrated, for example, in FIG. 15.

Reference is made to FIGS. 17 to 21 showing a pump arrangement inaccordance with a sixth embodiment of the present invention. The pumparrangement of FIGS. 17 to 21 has very close similarities to the pumparrangement shown in FIGS. 11 to 14 and can be used in directsubstitution thereof. The pump arrangement shown in FIG. 17 is identicalto the pump arrangement as shown in FIG. 14 but for two notabledifferences. In FIG. 14, the driving member 91 and the driven member 90are frictionally engaged with frictional forces preventing disengagementunless an applied tension force parallel the axes is greater than athreshold tension force. In the embodiment of FIG. 17, the drivingmember 91 and the driven member 90 are mechanically engaged throughfrangible members 500 and 501 that sever when the applied tension forceparallel the first axis is greater than the threshold tension parallelthe first axis. The use of frangible members to provide the releasablejuncture arrangement 92 in the embodiment of FIGS. 17 to 21 is a firstdifference between FIG. 17 and FIG. 14.

A second difference is that in FIG. 17 the second chamber-forming member136 and the second piston pump 130 including the second piston element142 are coaxial about the center axis 139. The second fluid socket 145is also coaxial about the center axis 139 and leads directly coaxiallyinto the mixing chamber 225.

The first chamber-forming member 36, the first piston pump 30 and thefirst piston element 42 as well as the first fluid socket 143 aredisposed about a first axis 74 parallel to the center axis 139. Thefirst fluid socket 143 is formed as a portion of the outer member 172 soas to carry the first fluid socket 143 with a first portion 502 of afirst fluid outlet port 149 extending axially outwardly then radiallyinwardly to sealably engage with a second portion 504 of the first fluidtransfer port 150 that extends radially through the intermediate stemportion 170 into the mixing chamber 225.

Referring to FIG. 19, axially outwardly from the bridge member 142, thefirst stem 78 is provided with a radially inwardly extending channelway510 which reduces a cross-sectional area of the stem 78 to form theannular frangible portion 500 which separates an axially inward portion512 of the stem 78 from an axially outward portion 513 of the stem.Similarly, the second stem 178 is provided with a radially inwardlyextending channelway 511 which reduces a cross-sectional area of thestem 178 to form the annular frangible portion 501 which separates anaxially inward portion 514 of the stem 178 from an axially outwardportion 515 of the stem 178. The annular frangible portions 500 and 501are selected such that each of the axially inner stem portions 512 and514 and axially outer stem portions 513 and 515 are mechanically engagedwith one of the frangible members with the frangible members to severwhen applied tension forces parallel the axis are greater than athreshold tension parallel the axis.

FIG. 20 schematically illustrates a condition of the first pistonelement 42 and the second piston element 142 together with the bridgemember 141 after the two annular severable portions 500 and 501 havebeen severed showing the two axially outer severable portions 513 and515 uncoupled from the axially inward portions 512 and 514 of theirrespective stems 78, 178.

In accordance with the embodiment of FIGS. 17 to 21, the driven member90 comprises the bridge member 141 together with the first pistonelement 42 and the second piston element 142 axially inwardly from theannular severable portions 500 and 501 on the stems 78, 178.

Referring to FIGS. 17 and 18, the axially outer ends of the outerportion 513 of the first stem 78 forms a plug that is coaxially receivedwithin the first fluid socket 143 in a friction fit engagement thatprevents removal under axially directed forces experienced during normaloperation of the pump arrangement. Similarly, the axially outer portion515 of the second stem 178 carries a plug that is frictionally engagedwithin the second fluid socket 146 against removal under axiallydirected forces experienced during normal operation of the pump. FIG. 17illustrates a coupled condition of the releasable juncture arrangement92 with the annular severable portions 500 and 501 intact. From theposition of FIG. 17 with the first float 32 in a closed position,continued movement of the outer member 172 by the actuator results in avacuum being created which will apply axially directed forces to thedriven member 90 sufficient to sever both the severable portions 500 and501 to assume a condition as shown in FIG. 18 with the releasablejuncture arrangement 92 uncoupled.

As can be seen in FIG. 18, the axially outer driving member 91 may beconsidered to be the combination of the intermediate stem portion 170,the outer member 172 and each of the axially outer portions 513 and 515of the stems 78, 178 axially outwardly from the annular severableportions 500 and 501.

In the embodiment of FIGS. 17 to 21, the outer portions 513 and 515 ofthe stems 78, 178 are illustrated as being received in a friction fitagainst removal within the first fluid socket 143 and the second fluidsocket 145. This coupling, however, may be by other means includinggluing, adhesion or fusion.

In the embodiment of FIGS. 17 to 21, rather than having two severableportions 500 and 501, merely one severable portion might be provided,for example, on the second stem 178 and the axially outer end of thefirst stem 78 may be received within the first fluid socket 143 ineither merely a sealing engagement or in a friction fit engagement.Thus, the releasable juncture arrangement 92 may be provided by acombination of use of frangible members, friction fit couplings andsealable sliding couplings.

A preferred use of the invention in accordance with the presentinvention is for the delivery of at least two fluids, a first liquid 17from a first reservoir and a second liquid 117 from a second reservoirin which the first liquid is different than the second liquid. Onepreferred arrangement is with the dispenser 10 comprising a dispenser ofhand cleaning fluids in which the first fluid is a concentrated liquidsuch as a concentrated liquid soap or a concentrated disinfectant andthe second fluid is a diluent for the first fluid such as, for example,water for a liquid soap or a water and alcohol diluent for a liquiddisinfectant. However, many other fluids may be used without departingfrom the scope of the present invention. The fluids may comprisecleaners, soaps, disinfectants, insecticides, beverages, oils andcondiments. As to the particular nature of the fluid, the fluids need tobe adequately flowable through each of the successive pumps withoutundue buildup of vacuum pressures inside the pumps other than conditionswhere uncoupling of the releasable juncture arrangement is desired. Thefluids thus may be liquids or other flowable material includingparticulate matter, creams such as hand creams and suntan lotions, haircreams, shampoo and the like.

In accordance with the present invention, the cartridge 14 is preferablya removable and replaceable cartridge for use in a dispenser 10 such asa soap dispenser. This is not necessary, however. The pump arrangement18 may be a permanent fixture within a dispenser 10 and the first andsecond reservoirs 16 suitably removable and replaceable. As well, eachof the reservoirs 16 may be adapted for refilling.

A pump arrangement in accordance with the present invention may be usedas a primary mechanism to prevent operation of a pump to dispense liquidafter a reservoir containing the liquid is empty. The pump arrangementin accordance with the present invention may be utilized in conjunctionwith other systems and arrangements towards monitoring whether or not areservoir may be empty of a fluid to be dispensed. For example, adispenser may include in addition to the pump arrangement, varioussensors and the like to determine if a reservoir is empty of fluid andto discontinue dispensing. The present invention, however, provides anadvantageous mechanical arrangement for preventing the continueddispensing of fluid from one or more reservoirs when any one of thereservoirs is empty of fluid. The pump arrangement in accordance withthe present invention does not require any electronic components and isadapted for use merely in a manually operated dispenser.

The first embodiment in FIG. 1 schematically illustrates the use of anelectric motor 60 to move the actuator plate. Motorized movement of anactuator plate may adopt systems such as that disclosed in U.S. Pat. No.8,071,933 to Ophardt et al, issued Dec. 6, 2011, the disclosure of whichis incorporated herein by reference.

The preferred embodiments illustrate the coupling and uncoupling of theengagement flange 72 with the actuator plate 52. Various arrangementsfor such coupling and uncoupling may be provided as, for example,including those disclosed in U.S. Pat. No. 8,113,388 to Ophardt et al,issued Feb. 14, 2012, the disclosure of which is incorporated herein byreference.

In each of the preferred embodiments, each of the piston pumps has beenillustrated as having a structure very similar to that disclosed in U.S.Pat. No. 5,975,360 to Ophardt, issued Nov. 2, 1999, the disclosure ofwhich is incorporated herein by reference. In these pumps, a separateone-way valve has been provided. However, the provision of a separateone-way valve is not necessary and, as disclosed in above-noted U.S.Pat. No. 5,975,360, by the provision of an additional disc inward fromthe inner disc 90 to be received in a smaller diameter inner portion ofthe dispensing chamber 36, the separate one-way valve 44 may beeliminated. An arrangement such as disclosed in FIG. 13 of U.S. Pat. No.5,975,360 could be utilized as a piston pump without the need for theone-way valve as a separate component.

In the third embodiment of the pump arrangement 18 as illustrated inFIG. 11, an arrangement is provided by which an air pump 196simultaneously discharges air with the discharge of liquid from one ormore liquid reservoirs so as to provide a foam comprising a mixture ofone or more of the liquids and air. In the arrangement of FIG. 12, twoliquids are discharged into a mixing chamber 225 which mixture of thetwo liquids is then mixed with air and passed through the foam generatorchamber 185 to provide a foam of the mixed liquids and air. The outerstem portion 173 could be modified such that merely one of the liquidsis mixed with air to form a foam and the other liquid is delivered tothe discharge outlet 89 without passing through the foam generatorchamber 185. An arrangement as shown in FIG. 12 could be modified toprovide a single reservoir 16 with the liquid from the single reservoirmixed with air and discharged as a foam.

In the embodiment of FIG. 11, the open end of the first dispensingchamber 38 opens into the inner end of the air chamber 168 and the openend of the second dispensing chamber 138 opens into the inner end of theair chamber 168. A mixing chamber 225 is provided affixed to the drivingmember 91. The mixing chamber 225 receives the first fluid 17 from thefirst pump 30 and the second fluid 117 from the second pump 130 and airfrom the air pump mixing the first fluid, the second fluid and the airto produce an air and fluid mixture and directing the air and fluidmixture into the foam generator chamber 135 and hence out the dispensingoutlet 89.

The pump arrangement of the first embodiment is illustrated in FIGS. 1to 5 with the reservoir having a suitable vent opening 21 to vent thereservoir to the atmosphere and let the level of the fluid 17 drop to alevel that each float 32 moves from an open condition to a closedcondition. Each of the reservoirs 16, 116 in FIGS. 7 and 11 is unventedbut are provided to include at least some air or other gas. Preferably,when initially filled with their respective liquid, some air is providedin the reservoirs such as up to 10%, preferably, 3 to 10% as is typicalof many filling operations. The reservoirs in FIGS. 7 and 11 may beuncollapsible or collapsible. Preferably, the reservoirs in FIGS. 7 and11 are collapsible and collapse as their liquid is drawn from thereservoirs. The threshold vacuum required to uncouple the releasablejuncture arrangement 92 is selected to be greater than the vacuumrequired to draw liquid out from each reservoir.

In accordance with the embodiment of the present invention of FIG. 16,the pump arrangement 18 is shown for use with a reservoir which is notvented and does not contain any air or gas and permits a vacuum to bebuilt up in the reservoir as the reservoir becomes emptied of the fluidand with vacuum is sufficient to uncouple the releasable juncturearrangement 92. With the collapsible bag for a reservoir as in FIG. 14,the fluid can easily be drawn from the reservoir until it is emptywithout the need to create any substantial vacuum to draw liquid fromthe bag. The vacuum required to draw liquid out from the reservoir ofFIG. 16 needs to be less than the threshold vacuum required to uncouplethe releasable juncture arrangement 92 at least until the reservoir isempty of liquid.

When, as in FIG. 16, a reservoir is an unvented collapsible reservoirwithout any gas in the reservoir, a float valve is unnecessary but maystill be included. Avoiding the float valve has the advantage ofavoiding the need to have the pump arrangement provide the float valveto be orientated so that the float 32 will float upward in the fluid 17to the open condition and move down under gravity to sit on the floatvalve seat 34 under gravity in the closed condition.

The preferred embodiments illustrate the releasable juncture arrangement92 as including a socket on the driving member 91 and a plug on thedriven member 90. Of course, a socket could be provided on the drivenmember 90 and a plug on the driving member. Various other mechanicalarrangements providing for a releasable frictional engagement of thedriving member 91 and the driven member 90 may be utilized which areovercome by axially directed tension forces applied across the juncture.

In the preferred embodiments, the float valves 28, 128 as upstream fromthe one-way valves 44, 144, however, this is not necessary. The floatvalves 28, 128, may be provided intermediate the inner end of the pistonelements 42, 142 and the respective one one-way valves 44, 144.

In the preferred embodiments the floats 32, 132 are shown as spherical.This is not necessary and the floats may have varying shapes andconfigurations with complementary cage structures.

While the invention has been described with reference to the preferredembodiments, many modifications and variations will now occur to personsskilled in the art. For a definition of the invention, reference is madeto the following claims.

We claim:
 1. A pump arrangement comprising: a first piston pump having afirst chamber and a first piston reciprocally movable along a first axisin the first chamber to draw a first fluid into the first chamber from afirst reservoir through a first conduit opening into the first chamberand discharge the first fluid out a first outlet, wherein reciprocalmovement of the first piston discharges the first fluid from the firstreservoir until the first reservoir is empty of the first fluid whereinfurther reciprocal movement of the first piston creates a vacuumcondition in the first chamber axially inward of the first piston, adriving member movable reciprocally parallel to the first axis, thedriving member adapted to be coupled to an actuator which moves thedriving member reciprocally parallel to the first axis, a releasablejuncture arrangement releasably coupling the driving member and thefirst piston together, the releasable juncture arrangement having acoupled condition and an uncoupled condition, in the coupled condition,the releasable juncture arrangement couples the driving member and thefirst piston together such that reciprocal movement of the drivingmember parallel the first axis moves the first piston parallel the firstaxis in unison, in the uncoupled condition, the releasable juncturearrangement does not couple the driving member and the first pistontogether such that reciprocal movement of the driving member parallelthe first axis does not move the first piston rendering the first pistonpump inoperative to discharge the first fluid by movement of the drivingmember, with the releasable juncture arrangement in the coupledcondition, when the vacuum condition in the first chamber is greaterthan a threshold separation vacuum, the releasable juncture arrangementassumes the uncoupled condition.
 2. The pump arrangement of claim 1including: a first one-way inlet valve across the first conduit, thefirst one-way inlet valve providing for flow of the first fluid from thefirst reservoir to the first chamber but preventing flow of the firstfluid from the first chamber to the first reservoir, and wherein thefirst reservoir is unvented and collapsible.
 3. The pump arrangement ofclaim 1 including: a first float valve across the first conduit betweenthe first reservoir and the first chamber, the first float valveincluding a first float movable between an open condition and a closedcondition, the first float buoyant in the first fluid, the first floatassuming the open condition when a level of the first fluid in the firstconduit is above a predetermined first fluid float level, the firstfloat assuming the closed condition when the level of the first fluid inthe first conduit is at or below the predetermined first fluid floatlevel, with the first float in the open condition, the first float valvepermitting for flow in the first conduit from the first reservoir to thefirst chamber, with the first float in the closed condition, the firstfloat valve preventing flow in the first conduit from the firstreservoir to the first chamber, with the first float in the closedcondition, reciprocal movement of the first piston creates the vacuumcondition in the first chamber between the first float valve and thefirst piston.
 4. The pump arrangement of claim 3 wherein the firstreservoir is vented to the atmosphere.
 5. The pump arrangement of claim3 including: a first one-way inlet valve across the first conduit, thefirst one-way inlet valve providing for flow of the first fluid from thefirst reservoir to the first chamber but preventing flow of the firstfluid from the first chamber to the first reservoir, the first floatvalve across the first conduit between the first reservoir and the firstone-way inlet valve.
 6. A pump arrangement as claimed in claim 1including: a second piston pump having a second chamber and a secondpiston reciprocally movable along a second axis in the second chamber todraw a second fluid into the second chamber from a second reservoirthrough a second conduit opening into the second chamber and dischargethe second fluid out a second outlet, the second axis parallel to thefirst axis, wherein reciprocal movement of the second piston dischargesthe second fluid from the second reservoir until the second reservoir isempty of the second fluid wherein further reciprocal movement of thesecond piston creates a vacuum condition in the second chamber axiallyinward of the second piston, a coupling bridge member mechanicallylinking the first piston and the second piston together to form a drivenmember carrying the first piston and second piston mechanically linkedwith the bridge member for movement in unison parallel the first axis,the driving member coupled to the driven member by the releasablejuncture arrangement, in the coupled condition of the releasablejuncture arrangement, the releasable juncture arrangement securing thedriving member and the driven member together for reciprocal movementalong the first axis in unison, in the uncoupled condition of thereleasable juncture arrangement, the movement of the driving member doesnot move the driven member rendering both the first piston pumpinoperative to discharge the first fluid by movement of the drivingmember and the second piston pump inoperative to discharge the secondfluid by movement of the driving member, with the releasable juncturearrangement in the coupled condition, when either the vacuum conditionin the first chamber is greater than the threshold separation vacuum orthe vacuum condition in the second chamber is greater than the thresholdseparation vacuum, the releasable juncture arrangement assumes theuncoupled condition.
 7. The pump arrangement of claim 6 including: afirst one-way inlet valve across the first conduit, the first one-wayinlet valve providing for flow of the first fluid from the firstreservoir to the first chamber but preventing flow of the first fluidfrom the first chamber to the first reservoir, and a second one-wayinlet valve across the second conduit, the second one-way inlet valveproviding for flow of the second fluid from the second reservoir to thesecond chamber but preventing flow of the second fluid from the secondchamber to the second reservoir, and wherein the first reservoir isunvented and collapsible, and the second reservoir is unvented andcollapsible.
 8. The pump arrangement of claim 6 including: a first floatvalve across the first conduit between the first reservoir and the firstchamber, the first float valve including a first float movable betweenan open condition and a closed condition, the first float buoyant in thefirst fluid, the first float assuming the open condition when a level ofthe first fluid in the first conduit is above a predetermined firstfluid float level, the first float assuming the closed position when thelevel of the first fluid in the first conduit is at or below thepredetermined first fluid float level, with the first float in the opencondition, the first float valve permitting for flow in the firstconduit from the first reservoir to the first chamber, with the firstfloat in the closed condition, the first float valve preventing flow inthe first conduit from the first reservoir to the first chamber, withthe first float in the closed condition, reciprocal movement of thefirst piston creates the vacuum condition in the first chamber betweenthe first float valve and the first piston, a second float valve acrossthe second conduit between the second reservoir and the second chamber,the second float valve including a second float movable between an opencondition and a closed condition, the second float buoyant in the secondfluid, the second float assuming the open condition when a level of thesecond fluid in the second conduit is above a predetermined second fluidfloat level, the second float assuming the closed condition when thelevel of the second fluid in the second conduit is at or below thepredetermined second fluid float level, with the second float in theopen condition, the second float valve permitting for flow in the secondconduit from the second reservoir to the second chamber, with the secondfloat in the closed condition, the second float valve preventing flow inthe second conduit from the second reservoir to the first chamber, withthe second float valve in the closed condition, reciprocal movement ofthe second piston creates the vacuum condition in the second chamberbetween the second float valve and the second piston.
 9. The pumparrangement of claim 8 wherein the first reservoir is vented to theatmosphere and the second reservoir is vented to the atmosphere.
 10. Thepump arrangement of claim 9 including: a first one-way inlet valveacross the first conduit, the first one-way inlet valve providing forflow of the first fluid from the first reservoir to the first chamberbut preventing flow of the first fluid from the first chamber to thefirst reservoir, the first float valve across the first conduit betweenthe first reservoir and the first one-way inlet valve, a second one-wayinlet valve across the second conduit, the second one-way inlet valveproviding for flow of the second fluid from the second reservoir to thesecond chamber but preventing flow of the second fluid from the secondchamber to the second reservoir, the second float valve across thesecond conduit between the second reservoir and the second one-way inletvalve.
 11. The pump arrangement of claim 4 including: a first one-wayinlet valve across the first conduit, the first one-way inlet valveproviding for flow of the first fluid from the first reservoir to thefirst chamber but preventing flow of the first fluid from the firstchamber to the first reservoir, the first float valve across the firstconduit between the first reservoir and the first one-way inlet valve.12. The pump arrangement of claim 7 wherein the first reservoir isvented to the atmosphere and the second reservoir is vented to theatmosphere.
 13. The pump arrangement of claim 8 including: a firstone-way inlet valve across the first conduit, the first one-way inletvalve providing for flow of the first fluid from the first reservoir tothe first chamber but preventing flow of the first fluid from the firstchamber to the first reservoir, the first float valve across the firstconduit between the first reservoir and the first one-way inlet valve, asecond one-way inlet valve across the second conduit, the second one-wayinlet valve providing for flow of the second fluid from the secondreservoir to the second chamber but preventing flow of the second fluidfrom the second chamber to the second reservoir, the second float valveacross the second conduit between the second reservoir and the secondone-way inlet valve.
 14. The pump arrangement as claimed in claim 1wherein the driving member and the first piston are mechanically engagedthrough a frangible member that severs when an applied tension forceparallel the first axis is greater than a threshold tension forceparallel the first axis.
 15. The pump arrangement as claimed in claim 6wherein the driving member and the driven member are mechanicallyengaged through a frangible member that severs when an applied tensionforce parallel the first axis is greater than a threshold tension forceparallel the first axis.
 16. The pump arrangement as claimed in claim 1wherein the driving member and the driven member are frictionallyengaged with frictional forces preventing disengagement unless anapplied tension force parallel the first axis is greater than thethreshold tension force parallel the first axis.
 17. The pumparrangement as claimed in claim 10 wherein the driving member and thefirst piston are mechanically engaged through a frangible member thatsevers when the applied tension force parallel the first axis is greaterthan a threshold tension force parallel the first axis.
 18. The pumparrangement as claimed in claim 13 wherein the driving member and thedriven member are mechanically engaged through a frangible member thatsevers when an applied tension force parallel the first axis is greaterthan a threshold tension force parallel the first axis.
 19. The pumparrangement as claimed in claim 6 wherein the driving member and thedriven member are frictionally engaged with frictional forces preventingdisengagement unless an applied tension force parallel the first axis isgreater than the threshold tension force parallel the first axis. 20.The pump arrangement as claimed in claim 10 wherein the driving memberand the driven member are frictionally engaged with frictional forcespreventing disengagement unless an applied tension force parallel thefirst axis is greater than the threshold tension force parallel thefirst axis.